A growing season is the period of the year when crops and other plants grow successfully. The length of a growing season varies from place to place. Most crops need a growing season of at least 90 days.

In tropical regions, where it is warm year-round, the growing season can last the entire year. In some tropical places, however, the growing season is interrupted by a rainy season. During this time, it is too wet to grow crops. Coffee, which grows in tropical climates, has this type of varied growing season. In Colombia, coffee is harvested all year. In Indonesia, heavy rains often interrupt the coffee growing season.

In other tropical places, it is sometimes too dry for crops to grow. The tropical region of northern Africa, called the Sahel, experiences frequent periods of drought. The Sahel is a transition zone between the Sahara Desert in the north and the savanna in the south. Due to dramatic weather patterns, the prospect of a successful harvest in the Sahel is highly uncertain.

In temperate regions, which have warm summers and cold winters, the length of the growing season depends mostly on temperature. Some growing seasons last as long as eight months. Europe and most of the Americas enjoy long growing seasons like this. The farther away a place is from the Equator, the shorter the growing season. In regions near the poles, the growing season is sometimes less than two months. The U.S. state of Alaska has an average growing season of only 105 days.

Elevation, or the height above sea level, also affects the growing season. This is because higher elevations usually have colder temperatures. High in the Sierra Nevada mountains in the U.S. state of California, the growing season lasts only 50 days, but along the state's southern coast, the growing season lasts 365 days.

There are two ways to determine the growing season. In temperate regions, the growing season is usually calculated by the average number of days between the last frost in spring and the first severe frost in autumn. The growing season can also be determined by the average number of days that the temperature rises high enough for a particular crop to sprout and grow. This measurement varies depending upon the crop. For rice to grow, the temperature must be at least 20 degrees Celsius (68 degrees Fahrenheit). Wheat, however, will sprout at just 5 degrees Celsius (40 degrees Fahrenheit).

growing season
The largest cabbage ever recorded—almost 57 kilograms (126 pounds)—was a product of Alaska's short but sunny growing season.

Alaska's Growing Season
Alaska has a very short growing season, only 105 days, on average. However, the Alaskan growing season does not have dark nightsthe Arctic is tilted toward the sun and plants grow in almost 24 hours of sunlight. In a growing season months shorter than the rest of the country, Alaskas gardeners grow some of the largest produce75-pound cabbages, 100-pound kale and 1,000-pound pumpkins.

Noun

region at Earth's extreme north, encompassed by the Arctic Circle.

cabbage
Noun

leafy green vegetable.

calculate
Verb

to reach a conclusion by mathematical or logical methods.

climate
Noun

all weather conditions for a given location over a period of time.

Noun

edge of land along the sea or other large body of water.

coffee
Noun

plant native to Africa whose dried berries and seeds are used for a drink of the same name.

Noun

agricultural produce.

determine
Verb

to decide.

dramatic
Adjective

very expressive or emotional.

Noun

period of greatly reduced precipitation.

Noun

height above or below sea level.

Noun

imaginary line around the Earth, another planet, or star running east-west, 0 degrees latitude.

frequent
Adjective

often.

Noun

thin coat of ice covering objects when the dew point is below freezing.

growing season
Noun

period in the year when crops and other plants grow rapidly.

harvest
Noun

the gathering and collection of crops, including both plants and animals.

kale
Noun

leafy green vegetable.

pole
Noun

extreme north or south point of the Earth's axis.

produce
Noun

agricultural products such as vegetables and fruits.

pumpkin
Noun

edible orange gourd.

rainy season
Noun

time of year when most of the rain in a region falls.

rice
Noun

grass cultivated for its seeds.

Sahel
Noun

transition zone in northern Africa between the Sahara Desert in the north and the savanna ecosystems in the south.

savanna
Noun

type of tropical grassland with scattered trees.

Noun

base level for measuring elevations. Sea level is determined by measurements taken over a 19-year cycle.

severe
Adjective

harsh.

sprout
Verb

to begin to grow.

successfully
Adverb

having achieved or completed the goal.

temperate
Adjective

moderate.

Noun

degree of hotness or coldness measured by a thermometer with a numerical scale.

transition zone
Noun

area between two natural or artificial regions.

tropical
Adjective

existing in the tropics, the latitudes between the Tropic of Cancer in the north and the Tropic of Capricorn in the south.

varied
Adjective

diverse.

weather pattern
Noun

repeating or predictable changes in the Earth's atmosphere, such as winds, precipitation, and temperatures.

wheat
Noun

most widely grown cereal in the world.